1. Field
Embodiments disclosed herein relate to techniques for storing and transporting one or more probe cards. Such techniques include a probe card support insert for storing one or more probe cards, a container including the probe card support insert, a system including the container and the probe card support insert for transporting one or more probe cards, and a method for storing and transporting one or more probe cards.
2. Description of the Related Art
In general, a semiconductor fabrication process involves various process equipments and fabrication process steps to build individual integrated circuits in a wafer. Each of the individual integrated circuits are provided with one or more metal pads on the surface of the wafer's surface. Signals are passed to and from each of the individual integrated circuits through the one or more metal pads.
The semiconductor fabrication process includes a wafer testing step in which the individual integrated circuits in the wafer are tested for functional defects. The wafer testing step is performed before a die preparation step that cuts the wafer into separate dies each including semiconducting material on which a given integrated circuit is built.
In the wafer testing step, an electronic test system, a prober, and a probe card are used to test the individual integrated circuits in the wafer. The individual integrated circuits in the wafer are tested by a series of electrical test signals sent by the electronic test system. The probe card is an interface between the electronic test system and the wafer. The probe card provides an electrical path between the electronic test system and the metal pads of the individual integrated circuits in the wafer, thereby permitting the passing of signals between the electronic test system and the integrated circuits in the wafer. The probe card is effectively a custom connector that takes the universal pattern of a given electronic test system and translates the signals to connect to the metal pads on the surface of the wafer. The probe card includes a plurality of probe tips that can be moved into electrical and mechanical contact with the metal pads on the surface of the wafer. Signals between the electronic test system and the integrated circuits of the wafer are passed through the electrical connections formed by the probe tips and the metal pads. An integrated circuit's response to test signals passed from the electronic test system to the integrated circuit through the electrical connection formed by a probe tip and a metal pad of the integrated circuit indicates whether the integrated circuit was fabricated correctly or incorrectly. The probe card can have a plurality of probe tips to allow for efficient simultaneous testing of multiple integrated circuits on the wafer. Integrated circuits that are fabricated incorrectly can then be removed during the die preparation step.
In the wafer testing step, the prober holds the wafer and the probe card, and aligns the wafer and the probe card to bring the probe tips into electrical and mechanical contact with the metal pads on the surface of the wafer. As an example, for dynamic random-access memory (DRAM) devices and FLASH memory devices provided on the wafer, each of the metal pads can have a size of approximately 40-90 micrometers per side. Each probe tip of the probe card that is to be brought into contact with a corresponding metal pad has a size that is smaller than the size of the metal pad.
Probe cards are manufactured with high precision in order to ensure precise mechanical and electrical contact between each of a plurality of probe tips with corresponding and relatively small metal pads on the wafer under testing. Probe cards can be fragile and easily susceptible to damage due to the small size of the probe tips. Probe cards can cost approximately $6,000 to $250,000 to manufacture. Further, depending on the complexity of the probe card, remanufacturing and repairing a damaged probe card can take from a few days to a few weeks.
Several conventional approaches are used to store probe cards. Probe cards can be stored on card racks, which hold multiple probe cards. Individual probe cards can also be stored in molded probe card protectors to protect the probe card from accidental damage. The probe card protectors can protect the probe card during transportation, and can protect the probe card from direct contact with the card rack. Further, the probe card protectors can provide a protective environment to reduce exposure of the stored probe cards to environmental contaminants.
In the semiconductor fabrication process, it is sometimes necessary to transport a probe card from one cleanroom facility to another cleanroom facility. The transportation of the probe card can be a multi-step manual process. In an example of the multi-step manual process, a technician wearing a first cleanroom suit may retrieve the probe card from a first clean room, leave the first clean room, remove the first cleanroom suit, manually transport the probe card to a different location, put on a second cleanroom suit, wipe down the probe card, enter a second clean room, and load the probe card to a prober or store the probe card in a rack in the second clean room. This manual process can take 30 minutes, for example.
There exists a need for alternative techniques to store one or more probe cards in a manner to decrease the likelihood of damage to the one or more probe cards. Further, there exists a need for alternative techniques to more efficiently transport the one or more probe cards while decreasing the likelihood of damage to the one or more probe cards during transportation.